Electronic throttle control pedals are well-known in the art, and are being used with increasing frequency in vehicles due to the trend towards electronically controlled engines. Rather than employing a mechanical linkage to connect the throttle pedal with the vehicle's engine, electronic throttle pedals are electrically linked to the vehicle's ECU (Electronic Control Unit), which in turn controls throttle settings on the engine. These known throttle pedals employ an electronic sensor, typically a potentiometer, which converts mechanical movement of the throttle pedal into an electrical signal representative of the pedal position, and thus of the desired throttle setting. This signal, which may be in the form of a digital, analog or PWM format, is forwarded to the engine's ECU either by a discrete wire, or via a data bus along with other control signals.
Electronic throttle pedals of the type described above are traditionally mounted either on the floor of the vehicle's passenger compartment, or are suspended in a cantilever fashion from the vehicle's firewall. Because the electronic pedal position sensor is mounted directly on the mechanical pedal assembly, packaging issues sometimes arise in those applications where the available envelope of space for the pedal is small or narrow. Consequently, efforts have been made to design and layout the pedal components in a manner which yields a compact assembly of desired dimensions.
Most recently electronically controlled engines have found use in off-road and industrial vehicles such as, for example, fork lift trucks. In these applications, a different set of considerations control electronic pedal design because of the harsher operating environments and different functional requirements that apply to pedal design for these applications. For example, in the case of a fork lift truck, different parts of the pedal assembly, such as the electronic sensor my be exposed to the surrounding environment and are subject to physical impact, and component loading not typically found in on-road vehicle applications. Moreover, bulky pedal assemblies can present an obstacle on the floor of the vehicle that may interfere with the operator's movements, either in controlling the vehicle or mounting and dismounting the vehicle.
The present invention provides an improvement in electronic control throttle pedal designs which is particularly suited for off-road and industrial vehicle applications where a simplified, low profile pedal is desirable.